Portable chain saw with detachable guards



1954 E. A. JAKKU 2,698,034

PORTABLE CHAIN SAW WITH DETACHABLE GUARDS Filed Feb. 20, 1950 2 Sheets-Sheet l INVENTOR EINO A. JAKE \U Z; I0 I BY ATTORNEY Dec. 28, 1954 E. A. JAKKU PORTABLE CHAIN SAW WITH DETACHABLE GUARDS Filed Feb. 20. 1950 2 Sheets-Sheet 2 INVENTOR El NO. A. JAKKU ATTORNEY United States Patent PORTABLE CHAIN SAW WITH DETACHABLE GUARDS Eino A. Jakku, Hood River, Oreg.

Application February 20, 1950, Serial No. 145,151

1 Claim. (Cl. 143-32) The primary object of this invention is. to adapt a chain saw to the pruning of trees, cutting of branches and the like.

I have found that by locating guards on the blade or frame of a chain saw over which the cutting chain is trained at intervals throughout its length, the said bars extending on either side of the chain and beyond both edges of the frame a sufficient distance to embrace the limbs of trees, that a chain saw will work very effectively in the trimming of trees, as well as cutting branches.

My new and improved pruning saw is adapted to either internal combustion engines, electric or air power driven saws.

These and other incidental objects will be apparent in the drawings, specification and claim.

Referring to the drawings:

Figure 1 is a perspective view of a conventional type of internal combustion engine driven chain saw having my new and improved cutting guards mounted thereto.

Figure 2 is a fragmentary detail enlarged view of the frame, partially broken away illustrating the cutting chain in relation to my new and improved guards, showing how the guard holds the limb of the tree while being cut.

Figure 3 is an enlarged detail sectional view of the frame cutting chain illustrating the guards mounted thereon, this view being taken on line 3-3 of Figure 1.

Figure 4 illustrates my new and improved guards mounted to the frame of an electric driven chain saw.

Figure 5 illustrates how the saw assembly may be supported on a counterbalanced supported mounted on the bed of a truck.

Referring more specifically to the drawings:

In Figure 1, I have illustrated a conventional type of internal combustion engine 1, having the chain saw frame 2 secured thereto in the usual manner. The cutting chain is indicated at 3 mounted to the frame 2 and driven by the motor 1 by a sprocket not here shown, but which is of well known practice.

My invention consists of mounting the guards 4 to the frame 2 by any suitable means, as for instance the bolts 5. These guards may fit directly against the frame or they may be spaced therefrom by spacers not here shown, depending upon the width of the chain saw 3. The guards 4 extend outwardly on either side of the frame and beyond both edges of the frame and the cutting chain 3 mounted thereon. The guards may be spaced apart at any desired distance, depending upon the type of work to be performed by the saw on which they are mounted.

In the operation of the saw, referring to Figures 1, 2,

3 and 5, the frame is lowered over the limb 6 to be cut, the chain operating in the direction of the arrow will cause the limb 6 to move towards the guard 7 which will hold the said limb while the teeth 8 of the saw 3 cut through the said branch or limb.

Referring to Figure 5, I have found that supporting the chain saw assembly by the chain or cable 9, that it is much easier to operate the same around the tree. The lower end of the chain terminates in a clevice 10, which may have a roller 11 mounted therein and adapted to be mounted to the rectangular pipe 12 forming part of the motor unit. In this particular motor this pipe forms part of the motor in that it provides the oil reservoir for the motor. In motors not having this oil reservoir, a ring to take the place of the same may be mounted to the motor.

In the operation of the saw it can be readily understood how the same can be operated as illustrated in a vertical plane, or it can be rolled over on its side, the roller 11 rolling within the rectangular pipe 12 supporting the entire unit with ease.

The upper end of the chain 9 is fixedly secured to the end 13 of the boom 14. The boom 14 is pivotally mounted at 15 to the tripod 16. A counterbalancing weight 17 is mounted to the opposite end of the boom 14 and is so adjusted to balance the load of the chain saw assembly.

The internal combustion engine type of chain saw is admirably adapted to be used in connection with the tripod arrangement or for cutting of heavy limbs, while the electrical driven unit illustrated in Figure 4 is admirably adapted for the cutting of smaller limbs and not requiring a counterbalancing support.

I do not wish to be limited to the type of power applied to the saw, as my invention really consists in the mounting of the guards 4 to the cutting blade of the saw, so that the chain saw 3 can be used to cut the limbs of trees or brush by simply forcing the chain of the saw against the same.

What I claim is:

A portable saw comprising an elongated flat frame formed at one end with a motor support, a chain saw trained about the periphery of said frame, and a plurality of adjustable guard members longitudinally spaced along the axis of the frame and detachably secured to said frame, each member extending beyond either side of the frame and beyond the edges thereof, each of said members presenting a pair of work engaging surfaces one on either side of the frame and extending substantially perpendicularly beyond the chain, the opposed work engaging surfaces of adjacent members being substantially parallel to receive a work piece therebetween.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 741,874 Barnes Oct. 20, 1903 1,723,125 Bens Aug. 6, 1929 1,946,390 Christiansen Feb. 6, 1934 2,034,058 Sacrey Mar. 17, 1936 2,216,971 Farmer Oct. 8, 1940 2,327,233 Wolf Aug. 17, 1943 2,488,343 Standal Nov. 15, 1949 2,567,886 Mall et al Sept. 11, 1951 

